drm/rockchip: cdn-dp: Convert to drm bridge

Convert it to drm bridge driver, it will be convenient for us to
migrate the connector part to the display driver later.
Considering that some code depend on the connector, the following
changes have been made:
- Only process edid in &drm_bridge_funcs.edid_read(), so no need to
store additional edid info.
- Now cdn_dp_get_sink_capability() only focused on reading DPCD_REV.
- Update bpc info in cdn_dp_bridge_atomic_enable() instead of
cdn_dp_encoder_mode_set(). Actually, the bpc data will be used in
cdn_dp_bridge_atomic_enable().
- Switch to use DRM_BRIDGE_OP_DP_AUDIO helpers.

This patch also convert to use devm_drm_bridge_alloc() API.

Tested with RK3399 EVB IND board.

Signed-off-by: Chaoyi Chen <[e-mail]>
Signed-off-by: Heiko Stuebner <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]

drivers/gpu/drm/rockchip/cdn-dp-core.c

···
 #include <sound/hdmi-codec.h>
 
 #include <drm/display/drm_dp_helper.h>
+#include <drm/display/drm_hdmi_audio_helper.h>
 #include <drm/drm_atomic_helper.h>
+#include <drm/drm_bridge_connector.h>
 #include <drm/drm_edid.h>
 #include <drm/drm_of.h>
 #include <drm/drm_probe_helper.h>
···
 #include "cdn-dp-core.h"
 #include "cdn-dp-reg.h"
 
-static inline struct cdn_dp_device *connector_to_dp(struct drm_connector *connector)
+static inline struct cdn_dp_device *bridge_to_dp(struct drm_bridge *bridge)
 {
-	return container_of(connector, struct cdn_dp_device, connector);
+	return container_of(bridge, struct cdn_dp_device, bridge);
 }
 
 static inline struct cdn_dp_device *encoder_to_dp(struct drm_encoder *encoder)
···
 }
 
 static enum drm_connector_status
-cdn_dp_connector_detect(struct drm_connector *connector, bool force)
+cdn_dp_bridge_detect(struct drm_bridge *bridge)
 {
-	struct cdn_dp_device *dp = connector_to_dp(connector);
+	struct cdn_dp_device *dp = bridge_to_dp(bridge);
 	enum drm_connector_status status = connector_status_disconnected;
 
 	mutex_lock(&dp->lock);
···
 	return status;
 }
 
-static void cdn_dp_connector_destroy(struct drm_connector *connector)
+static const struct drm_edid *
+cdn_dp_bridge_edid_read(struct drm_bridge *bridge, struct drm_connector *connector)
 {
-	drm_connector_unregister(connector);
-	drm_connector_cleanup(connector);
-}
-
-static const struct drm_connector_funcs cdn_dp_atomic_connector_funcs = {
-	.detect = cdn_dp_connector_detect,
-	.destroy = cdn_dp_connector_destroy,
-	.fill_modes = drm_helper_probe_single_connector_modes,
-	.reset = drm_atomic_helper_connector_reset,
-	.atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
-	.atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
-};
-
-static int cdn_dp_connector_get_modes(struct drm_connector *connector)
-{
-	struct cdn_dp_device *dp = connector_to_dp(connector);
-	int ret = 0;
+	struct cdn_dp_device *dp = bridge_to_dp(bridge);
+	const struct drm_edid *drm_edid;
 
 	mutex_lock(&dp->lock);
-
-	ret = drm_edid_connector_add_modes(connector);
-
+	drm_edid = drm_edid_read_custom(connector, cdn_dp_get_edid_block, dp);
 	mutex_unlock(&dp->lock);
 
-	return ret;
+	return drm_edid;
 }
 
 static enum drm_mode_status
-cdn_dp_connector_mode_valid(struct drm_connector *connector,
-			    const struct drm_display_mode *mode)
+cdn_dp_bridge_mode_valid(struct drm_bridge *bridge,
+			 const struct drm_display_info *display_info,
+			 const struct drm_display_mode *mode)
 {
-	struct cdn_dp_device *dp = connector_to_dp(connector);
-	struct drm_display_info *display_info = &dp->connector.display_info;
+	struct cdn_dp_device *dp = bridge_to_dp(bridge);
 	u32 requested, actual, rate, sink_max, source_max = 0;
 	u8 lanes, bpc;
 
···
 	return MODE_OK;
 }
 
-static struct drm_connector_helper_funcs cdn_dp_connector_helper_funcs = {
-	.get_modes = cdn_dp_connector_get_modes,
-	.mode_valid = cdn_dp_connector_mode_valid,
-};
-
 static int cdn_dp_firmware_init(struct cdn_dp_device *dp)
 {
 	int ret;
···
 
 static int cdn_dp_get_sink_capability(struct cdn_dp_device *dp)
 {
-	const struct drm_display_info *info = &dp->connector.display_info;
 	int ret;
 
 	if (!cdn_dp_check_sink_connection(dp))
···
 		DRM_DEV_ERROR(dp->dev, "Failed to get caps %d\n", ret);
 		return ret;
 	}
-
-	drm_edid_free(dp->drm_edid);
-	dp->drm_edid = drm_edid_read_custom(&dp->connector,
-					    cdn_dp_get_edid_block, dp);
-	drm_edid_connector_update(&dp->connector, dp->drm_edid);
-
-	dp->sink_has_audio = info->has_audio;
-
-	if (dp->drm_edid)
-		DRM_DEV_DEBUG_KMS(dp->dev, "got edid: width[%d] x height[%d]\n",
-				  info->width_mm / 10, info->height_mm / 10);
 
 	return 0;
 }
···
 	dp->active = false;
 	dp->max_lanes = 0;
 	dp->max_rate = 0;
-	if (!dp->connected) {
-		drm_edid_free(dp->drm_edid);
-		dp->drm_edid = NULL;
-	}
 
 	return 0;
 }
···
 	return ret;
 }
 
-static void cdn_dp_encoder_mode_set(struct drm_encoder *encoder,
-				    struct drm_display_mode *mode,
-				    struct drm_display_mode *adjusted)
+static void cdn_dp_bridge_mode_set(struct drm_bridge *bridge,
+				   const struct drm_display_mode *mode,
+				   const struct drm_display_mode *adjusted)
 {
-	struct cdn_dp_device *dp = encoder_to_dp(encoder);
-	struct drm_display_info *display_info = &dp->connector.display_info;
+	struct cdn_dp_device *dp = bridge_to_dp(bridge);
 	struct video_info *video = &dp->video_info;
-
-	switch (display_info->bpc) {
-	case 10:
-		video->color_depth = 10;
-		break;
-	case 6:
-		video->color_depth = 6;
-		break;
-	default:
-		video->color_depth = 8;
-		break;
-	}
 
 	video->color_fmt = PXL_RGB;
 	video->v_sync_polarity = !!(mode->flags & DRM_MODE_FLAG_NVSYNC);
···
 	return drm_dp_channel_eq_ok(link_status, min(port->lanes, sink_lanes));
 }
 
-static void cdn_dp_audio_handle_plugged_change(struct cdn_dp_device *dp,
-					       bool plugged)
+static void cdn_dp_display_info_update(struct cdn_dp_device *dp,
+				       struct drm_display_info *display_info)
 {
-	if (dp->codec_dev)
-		dp->plugged_cb(dp->codec_dev, plugged);
+	struct video_info *video = &dp->video_info;
+
+	switch (display_info->bpc) {
+	case 10:
+		video->color_depth = 10;
+		break;
+	case 6:
+		video->color_depth = 6;
+		break;
+	default:
+		video->color_depth = 8;
+		break;
+	}
 }
 
-static void cdn_dp_encoder_enable(struct drm_encoder *encoder)
+static void cdn_dp_bridge_atomic_enable(struct drm_bridge *bridge, struct drm_atomic_state *state)
 {
-	struct cdn_dp_device *dp = encoder_to_dp(encoder);
+	struct cdn_dp_device *dp = bridge_to_dp(bridge);
+	struct drm_connector *connector;
 	int ret, val;
 
-	ret = drm_of_encoder_active_endpoint_id(dp->dev->of_node, encoder);
+	connector = drm_atomic_get_new_connector_for_encoder(state, bridge->encoder);
+	if (!connector)
+		return;
+
+	cdn_dp_display_info_update(dp, &connector->display_info);
+
+	ret = drm_of_encoder_active_endpoint_id(dp->dev->of_node, &dp->encoder.encoder);
 	if (ret < 0) {
 		DRM_DEV_ERROR(dp->dev, "Could not get vop id, %d", ret);
 		return;
···
 
 	ret = cdn_dp_enable(dp);
 	if (ret) {
-		DRM_DEV_ERROR(dp->dev, "Failed to enable encoder %d\n",
+		DRM_DEV_ERROR(dp->dev, "Failed to enable bridge %d\n",
 			      ret);
 		goto out;
 	}
···
 		goto out;
 	}
 
-	cdn_dp_audio_handle_plugged_change(dp, true);
-
 out:
 	mutex_unlock(&dp->lock);
 }
 
-static void cdn_dp_encoder_disable(struct drm_encoder *encoder)
+static void cdn_dp_bridge_atomic_disable(struct drm_bridge *bridge, struct drm_atomic_state *state)
 {
-	struct cdn_dp_device *dp = encoder_to_dp(encoder);
+	struct cdn_dp_device *dp = bridge_to_dp(bridge);
 	int ret;
 
 	mutex_lock(&dp->lock);
-	cdn_dp_audio_handle_plugged_change(dp, false);
 
 	if (dp->active) {
 		ret = cdn_dp_disable(dp);
 		if (ret) {
-			DRM_DEV_ERROR(dp->dev, "Failed to disable encoder %d\n",
+			DRM_DEV_ERROR(dp->dev, "Failed to disable bridge %d\n",
 				      ret);
 		}
 	}
···
 }
 
 static const struct drm_encoder_helper_funcs cdn_dp_encoder_helper_funcs = {
-	.mode_set = cdn_dp_encoder_mode_set,
-	.enable = cdn_dp_encoder_enable,
-	.disable = cdn_dp_encoder_disable,
 	.atomic_check = cdn_dp_encoder_atomic_check,
 };
 
···
 	return 0;
 }
 
-static int cdn_dp_audio_hw_params(struct device *dev,  void *data,
-				  struct hdmi_codec_daifmt *daifmt,
-				  struct hdmi_codec_params *params)
+static int cdn_dp_audio_prepare(struct drm_connector *connector,
+				struct drm_bridge *bridge,
+				struct hdmi_codec_daifmt *daifmt,
+				struct hdmi_codec_params *params)
 {
-	struct cdn_dp_device *dp = dev_get_drvdata(dev);
+	struct cdn_dp_device *dp = bridge_to_dp(bridge);
 	struct audio_info audio = {
 		.sample_width = params->sample_width,
 		.sample_rate = params->sample_rate,
···
 		audio.format = AFMT_SPDIF;
 		break;
 	default:
-		DRM_DEV_ERROR(dev, "Invalid format %d\n", daifmt->fmt);
+		drm_err(bridge->dev, "Invalid format %d\n", daifmt->fmt);
 		ret = -EINVAL;
 		goto out;
 	}
···
 	return ret;
 }
 
-static void cdn_dp_audio_shutdown(struct device *dev, void *data)
+static void cdn_dp_audio_shutdown(struct drm_connector *connector,
+				  struct drm_bridge *bridge)
 {
-	struct cdn_dp_device *dp = dev_get_drvdata(dev);
+	struct cdn_dp_device *dp = bridge_to_dp(bridge);
 	int ret;
 
 	mutex_lock(&dp->lock);
···
 	mutex_unlock(&dp->lock);
 }
 
-static int cdn_dp_audio_mute_stream(struct device *dev, void *data,
+static int cdn_dp_audio_mute_stream(struct drm_connector *connector,
+				    struct drm_bridge *bridge,
 				    bool enable, int direction)
 {
-	struct cdn_dp_device *dp = dev_get_drvdata(dev);
+	struct cdn_dp_device *dp = bridge_to_dp(bridge);
 	int ret;
 
 	mutex_lock(&dp->lock);
···
 	return ret;
 }
 
-static int cdn_dp_audio_get_eld(struct device *dev, void *data,
-				u8 *buf, size_t len)
-{
-	struct cdn_dp_device *dp = dev_get_drvdata(dev);
+static const struct drm_bridge_funcs cdn_dp_bridge_funcs = {
+	.atomic_duplicate_state = drm_atomic_helper_bridge_duplicate_state,
+	.atomic_destroy_state = drm_atomic_helper_bridge_destroy_state,
+	.atomic_reset = drm_atomic_helper_bridge_reset,
+	.detect = cdn_dp_bridge_detect,
+	.edid_read = cdn_dp_bridge_edid_read,
+	.atomic_enable = cdn_dp_bridge_atomic_enable,
+	.atomic_disable = cdn_dp_bridge_atomic_disable,
+	.mode_valid = cdn_dp_bridge_mode_valid,
+	.mode_set = cdn_dp_bridge_mode_set,
 
-	memcpy(buf, dp->connector.eld, min(sizeof(dp->connector.eld), len));
-
-	return 0;
-}
-
-static int cdn_dp_audio_hook_plugged_cb(struct device *dev, void *data,
-					hdmi_codec_plugged_cb fn,
-					struct device *codec_dev)
-{
-	struct cdn_dp_device *dp = dev_get_drvdata(dev);
-
-	mutex_lock(&dp->lock);
-	dp->plugged_cb = fn;
-	dp->codec_dev = codec_dev;
-	cdn_dp_audio_handle_plugged_change(dp, dp->connected);
-	mutex_unlock(&dp->lock);
-
-	return 0;
-}
-
-static const struct hdmi_codec_ops audio_codec_ops = {
-	.hw_params = cdn_dp_audio_hw_params,
-	.audio_shutdown = cdn_dp_audio_shutdown,
-	.mute_stream = cdn_dp_audio_mute_stream,
-	.get_eld = cdn_dp_audio_get_eld,
-	.hook_plugged_cb = cdn_dp_audio_hook_plugged_cb,
+	.dp_audio_prepare = cdn_dp_audio_prepare,
+	.dp_audio_mute_stream = cdn_dp_audio_mute_stream,
+	.dp_audio_shutdown = cdn_dp_audio_shutdown,
 };
-
-static int cdn_dp_audio_codec_init(struct cdn_dp_device *dp,
-				   struct device *dev)
-{
-	struct hdmi_codec_pdata codec_data = {
-		.i2s = 1,
-		.spdif = 1,
-		.ops = &audio_codec_ops,
-		.max_i2s_channels = 8,
-		.no_capture_mute = 1,
-	};
-
-	dp->audio_pdev = platform_device_register_data(
-			 dev, HDMI_CODEC_DRV_NAME, PLATFORM_DEVID_AUTO,
-			 &codec_data, sizeof(codec_data));
-
-	return PTR_ERR_OR_ZERO(dp->audio_pdev);
-}
 
 static int cdn_dp_request_firmware(struct cdn_dp_device *dp)
 {
···
 
 out:
 	mutex_unlock(&dp->lock);
-	drm_connector_helper_hpd_irq_event(&dp->connector);
+	drm_bridge_hpd_notify(&dp->bridge,
+			      dp->connected ? connector_status_connected
+					    : connector_status_disconnected);
 }
 
 static int cdn_dp_pd_event(struct notifier_block *nb,
···
 
 	drm_encoder_helper_add(encoder, &cdn_dp_encoder_helper_funcs);
 
-	connector = &dp->connector;
-	connector->polled = DRM_CONNECTOR_POLL_HPD;
-	connector->dpms = DRM_MODE_DPMS_OFF;
+	dp->bridge.ops =
+			DRM_BRIDGE_OP_DETECT |
+			DRM_BRIDGE_OP_EDID |
+			DRM_BRIDGE_OP_HPD |
+			DRM_BRIDGE_OP_DP_AUDIO;
+	dp->bridge.of_node = dp->dev->of_node;
+	dp->bridge.type = DRM_MODE_CONNECTOR_DisplayPort;
+	dp->bridge.hdmi_audio_dev = dp->dev;
+	dp->bridge.hdmi_audio_max_i2s_playback_channels = 8;
+	dp->bridge.hdmi_audio_spdif_playback = 1;
+	dp->bridge.hdmi_audio_dai_port = -1;
 
-	ret = drm_connector_init(drm_dev, connector,
-				 &cdn_dp_atomic_connector_funcs,
-				 DRM_MODE_CONNECTOR_DisplayPort);
-	if (ret) {
-		DRM_ERROR("failed to initialize connector with drm\n");
-		goto err_free_encoder;
+	ret = devm_drm_bridge_add(dev, &dp->bridge);
+	if (ret)
+		return ret;
+
+	ret = drm_bridge_attach(encoder, &dp->bridge, NULL, DRM_BRIDGE_ATTACH_NO_CONNECTOR);
+	if (ret)
+		return ret;
+
+	connector = drm_bridge_connector_init(drm_dev, encoder);
+	if (IS_ERR(connector)) {
+		ret = PTR_ERR(connector);
+		dev_err(dp->dev, "failed to init bridge connector: %d\n", ret);
+		return ret;
 	}
 
-	drm_connector_helper_add(connector, &cdn_dp_connector_helper_funcs);
-
-	ret = drm_connector_attach_encoder(connector, encoder);
-	if (ret) {
-		DRM_ERROR("failed to attach connector and encoder\n");
-		goto err_free_connector;
-	}
+	drm_connector_attach_encoder(connector, encoder);
 
 	for (i = 0; i < dp->ports; i++) {
 		port = dp->port[i];
···
 		if (ret) {
 			DRM_DEV_ERROR(dev,
 				      "register EXTCON_DISP_DP notifier err\n");
-			goto err_free_connector;
+			return ret;
 		}
 	}
 
···
 	schedule_work(&dp->event_work);
 
 	return 0;
-
-err_free_connector:
-	drm_connector_cleanup(connector);
-err_free_encoder:
-	drm_encoder_cleanup(encoder);
-	return ret;
 }
 
 static void cdn_dp_unbind(struct device *dev, struct device *master, void *data)
 {
 	struct cdn_dp_device *dp = dev_get_drvdata(dev);
 	struct drm_encoder *encoder = &dp->encoder.encoder;
-	struct drm_connector *connector = &dp->connector;
 
 	cancel_work_sync(&dp->event_work);
-	cdn_dp_encoder_disable(encoder);
 	encoder->funcs->destroy(encoder);
-	connector->funcs->destroy(connector);
 
 	pm_runtime_disable(dev);
 	if (dp->fw_loaded)
 		release_firmware(dp->fw);
-	drm_edid_free(dp->drm_edid);
-	dp->drm_edid = NULL;
 }
 
 static const struct component_ops cdn_dp_component_ops = {
···
 	int ret;
 	int i;
 
-	dp = devm_kzalloc(dev, sizeof(*dp), GFP_KERNEL);
-	if (!dp)
-		return -ENOMEM;
+	dp = devm_drm_bridge_alloc(dev, struct cdn_dp_device, bridge,
+				   &cdn_dp_bridge_funcs);
+	if (IS_ERR(dp))
+		return PTR_ERR(dp);
 	dp->dev = dev;
 
 	match = of_match_node(cdn_dp_dt_ids, pdev->dev.of_node);
···
 	mutex_init(&dp->lock);
 	dev_set_drvdata(dev, dp);
 
-	ret = cdn_dp_audio_codec_init(dp, dev);
+	ret = component_add(dev, &cdn_dp_component_ops);
 	if (ret)
 		return ret;
 
-	ret = component_add(dev, &cdn_dp_component_ops);
-	if (ret)
-		goto err_audio_deinit;
-
 	return 0;
-
-err_audio_deinit:
-	platform_device_unregister(dp->audio_pdev);
-	return ret;
 }
 
 static void cdn_dp_remove(struct platform_device *pdev)

drivers/gpu/drm/rockchip/cdn-dp-core.h

···
 #define _CDN_DP_CORE_H
 
 #include <drm/display/drm_dp_helper.h>
+#include <drm/drm_bridge.h>
 #include <drm/drm_panel.h>
 #include <drm/drm_probe_helper.h>
 #include <sound/hdmi-codec.h>
···
 struct cdn_dp_device {
 	struct device *dev;
 	struct drm_device *drm_dev;
-	struct drm_connector connector;
+	struct drm_bridge bridge;
 	struct rockchip_encoder encoder;
 	struct drm_display_mode mode;
 	struct platform_device *audio_pdev;
 	struct work_struct event_work;
-	const struct drm_edid *drm_edid;
 
 	struct mutex lock;
 	bool connected;
···
 	int active_port;
 
 	u8 dpcd[DP_RECEIVER_CAP_SIZE];
-	bool sink_has_audio;
-
-	hdmi_codec_plugged_cb plugged_cb;
-	struct device *codec_dev;
 };
 #endif  /* _CDN_DP_CORE_H */